1. Field of the Invention
The present invention relates to a printing system, and, more particularly, to a method of controlling a print job schedule that ensures efficient printing processes in a network printing system shared by multiple users or in a high-speed printing system, and a printing system using the method.
2. Description of the Related Art
In a general network printing system where one network printer is shared by multiple users, in response to a print command from a client computer, an internal printer driver is accessed to convert data format from graphic data of an application program, which is used to command printing, to data in page description language (PDL), which is interpretable by a target network printer. For example, a postscript (PS) printer driver transmits graphics, images, and text in various formats of different application programs through format conversion into PS language, and a printer command language (PCL) printer driver transmits graphics, images, and text in various formats of different application programs through format conversion into PCL language.
The network printer temporarily stores print job data, transmitted through a network from a user, in a reception buffer of a random access memory (RAM). A printing controller accesses a predetermined interpreter, for example, a PCL or PS interpreter, stored in a read-only memory (ROM) to convert the print job data to a printable data format and transmits the converted print job data to a printer engine.
In a conventional network printing system, only one interpreter operating area is reserved in RAM for each interpreter stored in ROM, regardless of the type of interpreter. However, such a printing environment causes the following problems. For example, assuming that user A gave a command to print a 100-page document a little earlier than user B who has a 1-page document to print, user B must wait until the 100-page document of user A is completely printed. Even if a document which user A needs to print includes only a few pages, if the document includes graphics or text of various fonts that burden an interpreter with complicated, repetitive operations, user B must wait a considerably long time until the print job for user A is terminated.
In a conventional printing system that is not shared by multiple users, assuming that a user has print job A, and print job B, if print job A which will take a long time to print is sent to the printing system before print job B, which is only one-page long, the user must wait until print job A is terminated or must abort printing print job A to obtain a printout for print job B in a short amount of time. Therefore, efficient, high-speed printing is virtually impossible.